The present invention relates to labeling machines. In particular, the present invention relates to machines that apply labels to cylindrical containers such as pails, drums and the like.
Many products are sold in cylindrical containers and drums, or xe2x80x9cpailsxe2x80x9d. Pails typically have accurate handles, or xe2x80x9cbailsxe2x80x9d, that run from one side near the top of the pail to the opposing side. These bails are attached to projections, sometimes called xe2x80x9cearsxe2x80x9d, near the tops of the pails just below the lids.
The pails are labeled with pre-printed labels carrying product information as well as the brand name of the product inside. These labels are applied to the pails using a cylindrical container labeling machine.
An example of a pail labeling machine is found in U.S. Pat. No. 4,591,403, issued to Anker Labelers Corp., in 1986.
There are several problems that can be encountered in pail labeling machines. First, the bails of the pails need to be vertical when the pail enters the labeling machine. The bail is used to orient the pail by lifting and turning the bail so that the label is attached at the right location on the pail. If the bail is not vertical, the label may not be attached at the right place, or the bail may be over the surface area where the label is to be placed.
The bails made by various manufacturers are not always of the same strength. If a bail were not strong enough, it might bend or twist out of shape, again potentially causing a malfunction of the machine or misalignment of the pail for labeling and reduced label wipe-on efficiency.
The rate of labeling depends in part on the speed of orientation and rotation. Orienting and turning the pails, using their handles, limits the speed at which the pails could be labeled.
Prior art labeling machines also used moving label magazines, which are slower, require more energy and have a potential for injury.
Prior art label delivery and transfer systems depend on the uniformity and tackiness of the glue for effective label picking and feeding and placement on the pails. If the glue was not sufficiently tacky, the label might not be picked out of the moveable label magazine immediately by the glue roller and consequently applied incorrectly, if applied at all. Finally, prior art labeling machines have been known to cause injury while operators attempt to correct the shortcomings addressed in the aforementioned paragraph.
Thus there remains a need for a pail labeler that addresses these shortcomings in the prior art.
According to its major aspects and broadly stated, the present invention is a cylindrical container labeling machine comprised of a horizontal conveyor, container orientation means at the front end of the conveyor, bail orientation means following the container orientation means, a stationary label magazine adjacent to the horizontal conveyor, label transfer means to move a label from the magazine into position on the conveyor and label application means to adhere the label to the container.
The container orientation means rotates the container using two pail-side-engaging, vertical conveyors moving at different, relative speeds. Each being driven by a separate motor. Preferably, the vertical conveyors operate in opposing directions. Once the machine senses that the container is properly oriented with the use of a sensor, detecting the projections which secure the bail, on the horizontal conveyor, both vertical conveyors commence to move at the same speed and in the same direction. The bail orienting means assures that the handle is on the side of the pail opposite that where the label is to be applied. Another need of the users of pails is to identify a xe2x80x9cBaby-in-the-bucketxe2x80x9d label, which is required by the government to be placed on all 5 gallon pails. This pail orientation means also ensures presence by this label using the means of orientation.
A feature of the present invention is the pail orientation means that does not depend on the strength or shape of the bail for orienting the pail only on its existence on opposite sides of the pail. This feature provides greater assurance that a variety of pails can be properly oriented before their labels are applied.
Another feature of the present invention is the label transfer mechanism. The present invention takes the labels from a stationary magazine and applies glue to them. The use of two feed rollers including two pivoting back pressure rollers to maintain alignment and non-slip contact between the label transferring system and the label helps to assure that the label will be applied correctly to the container.
Still another feature of the present invention is the brush to sweep the bail from the front of the pail as it moves along the horizontal conveyor to the rear of the pail. This feature provides a simple and reliable way of orienting the bail.
Still another feature of the present invention are the label gates, vertical endless conveyors with holes formed in their surfaces and with corresponding fans behind them to maintain a vacuum pressure on the opposing sides of the gates as the label is moved into position over the horizontal conveyor belt with respect to the oncoming container.
Other features and advantages of the present invention will be apparent to those skilled in the art from a careful reading of the Detailed Description of a Preferred Embodiment presented below and accompanied by the drawings.